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Indexed by:期刊论文

Date of Publication:2021-01-26

Journal:INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY

Volume:96

Issue:1-4

Page Number:643-655

ISSN No.:0268-3768

Key Words:CFRP; Stack composite; Oblique cutting; Sub-surface damage; Finite element analysis

Abstract:Fiber-metal stack composite has been widely used in various aerospace industry due to its enhanced mechanical properties. It is still a challenge to machine such stack composite, for the disparate nature of each stacked constituent and the complex interaction between two constituents. The CFRP (Carbon Fiber Reinforced Plastic) is prone to get sub-surface damage in the chip formation process, which affects the mechanical property of the workpiece. Meanwhile, the sub-surface damage varies obviously under different interaction caused by different stacking sequences, and is also strongly influenced by fiber orientations and cutting parameters. However, only experimental researches on CFRP/Ti stack composite machining cannot reveal the cutting characters of the interface region with the impact of the titanium completely. In contrast, numerical simulation could offer sufficient capabilities to overcome the limitations of the experimentation. In this study, a new contribution is provided to study the sub-surface damage of the interface region versus the interaction of stacked constituents, fiber orientation and cutting parameters via numerical approach. To this aim, a three-dimensional oblique cutting model is developed to simulate the chip formation process of cutting two stacked constituents simultaneously. Different constitutive models and failure criteria are implemented to construct the entire machining behaviors of the stack composite. Simulation results, cutting forces and sub-surface damage depths obtained match well with the experimental ones, which could verify the correctness of the established model. The numerical results highlight the significant effects of fiber orientations, cutting parameters and stacking sequences on the sub-surface damage in the interface region. The variation trends of sub-surface damage are distinct in different fiber orientations and stacking sequences. The research provides a guidance on reduction of the sub-surface damage in machining stack composites.